[Corinthian]

Originally Posted by Endoperez

I'm pretty sure "Beholder" name is not available for use without negotiating with Wizards of the Coast.
"They are one of the few classic Dungeons & Dragons monsters that Wizards of the Coast claims as Product Identity.[1]"

I understand it's legal to have an eye-monster that casts spell, as long as you don't call it a Beholder.

Wrong. You cant copyright fictional races or their names. In fact, Wizards of the Coasts themselves would not exist if it was not for this fact. WotC have replied in previous cases that races and rule-sets fall under the "you cant copyright rules and facts" exception in international copyright law. They do have copyright on characters, settings and similar things though.